ADA Tejas (LCA) News and Discussions

[Pulkit]

That is be a great news....
Eagerly waiting for the official announcement

That is past order, According to latest developments there will be 294 ..

There will be more updates to come, Including new production facility to produce no of fighters also official statement from IAF ..

 

[Kunal Biswas]

Firstly the Past order has to be completed with HAL capability to make 16 per year, To accomplish given numbers the second production line have to be open ( Gov or Pvt unknown ) sometime in Near future for remaining 14 squadron ..

The official mod statement is already given, But we may have to wait for IAF statement until the first order is complete ..

=====================

This poster is not official ..

 

[ersakthivel]

silent eagle F-15 a 4.5th gen fighter launching air to air missile from newly added external stealth pod,
such a combination can be added to tejas or any other 4.5th gen fighter with a clean config frontal RCS of below 0.5 meters,
giving them further edge over older 4th gen fighters like F-16 fighters, that have more than 1 sq meter as clean config frontal RCS.


tejas, rafale, typhoon are the 4.5th gen fighters that can use this type of external stealth pods to complement their clean config frontal RCS of below 0.3 meters,giving them the ability to remain undetected by opposing bigger 4th gen older fighters like f-16, f-15, mirage-2000 , mig-29, su-30 mki, j-10 which all have more than 1 sq meter frontal clean config RCS that can be detected before 100 Km by today's ASEA radar.

So these older fighters despite having more powerful radar wont be able to launch their longer range BVR first at these smaller clean config fighters belonging to 4.5 th gen.

 

[abhi_the _gr8_maratha]

T
ejas incorporates a highly reliable
quadruplex digital fly-by-wire Flight
Control System. The new generation
glass cockpit comprises Multi Function
Displays (MFD), Head Up Display (HUD)
and Stand by Instrumentation System
driven by Open Architecture Mission
and Display Computer. This provides
effective Human Machine Interface
(HMI).The advanced utility and health
management system provides system
health and warnings to the pilot
through a Open Architecture
Computer (OAC).

 

[Twinblade]

2511th flight on 18 Mar
TD1 : 233 , PV1: 242 , PV3: 381, LSP1: 74, LSP3: 195, LSP5: 252, TD2 : 305, PV2: 222, PV5: 36, LSP2: 293, LSP4: 110, LSP7: 79, NP1: 15, LSP8 : 74

2526th flight on 29 Mar
TD1 : 233, PV1: 242, PV3: 381, LSP1: 74, LSP3: 199, LSP5: 253, TD2 : 305, PV2: 222, PV5: 39, LSP2: 294, LSP4: 110, LSP7: 79, NP1: 19, LSP8 : 76

2543th flight on 29 April
TD1 : 233, PV1: 242, PV3: 381, LSP1: 74, LSP3: 200, LSP5: 259, TD2 : 305, PV2: 222, PV5: 40, LSP2: 294, LSP4: 110, LSP7: 85, NP1: 21, LSP8 : 77

2546th flight on 01 May
TD1 : 233, PV1: 242, PV3: 381, LSP1: 74, LSP3: 200, LSP5: 260, TD2 : 305, PV2: 222, PV5: 40, LSP2: 294, LSP4: 111, LSP7: 85, NP1: 22, LSP8 : 77

 

[sathya]

silent eagle F-15 a 4.5th gen fighter launching air to air missile from newly added external stealth pod,
such a combination can be added to tejas or any other 4.5th gen fighter with a clean config frontal RCS of below 0.5 meters,
giving them further edge over older 4th gen fighters like F-16 fighters, that have more than 1 sq meter as clean config frontal RCS.


tejas, rafale, typhoon are the 4.5th gen fighters that can use this type of external stealth pods to complement their clean config frontal RCS of below 0.3 meters,giving them the ability to remain undetected by opposing bigger 4th gen older fighters like f-16, f-15, mirage-2000 , mig-29, su-30 mki, j-10 which all have more than 1 sq meter frontal clean config RCS that can be detected before 100 Km by today's ASEA radar.

So these older fighters despite having more powerful radar wont be able to launch their longer range BVR first at these smaller clean config fighters belonging to 4.5 th gen.

Actually Tejas mk 2 can take advantage of this stealth pod, since it's hard points are limited and has extra power, wouldn't affect weapon payload at all..

 

[ersakthivel]

Actually Tejas mk 2 can take advantage of this stealth pod, since it's hard points are limited and has extra power, wouldn't affect weapon payload at all..

both tejas mk-1 and mk-2 (of course weapon load may vary)can take advantage of it. in US the external stealth pods , since rafale, super hornet, f-15 eagle will one day carry them irrespective of their TWR.

But these external weapon pods are mostly used in air to air interception missions till now, since weight of air to air missiles are far lesser than heavy ground bombs weight is not a big issue.

Actually there are some hilarious discussions going on over many forums over the missing eight hard point of tejas.

Now ask those guys one simple questions, with 9 ton load carrying capacity rafale has 14 hard points.
With 3.7 ton capacity tejas mk-1 has seven hard points,

With 5 ton load carrying caapcity tejas mk-2 will have 7 hard points. So why people are disappointed with this?

You can rest assure that there will be no reply from many "fake experts claiming superior knowledge."

Also in the same way there are many guys who claim to have "specialized knowledge" of tejas's excess drag which is causing so many problems for tejas in their imagination.

Ask them one simple question,

With a thrust to weight (empty weight +half internal fuel+ two WVR missiles weight taken as norm) ratio of 1.2

rafale has a top speed of mach 1.8 at its service ceiling (15235 meters),

and 1390 km per hour at sea level,

Vs

With a Thrust to weight ratio (empty weight +half internal fuel+ two WVR missiles weight taken as norm) of 0.97,

tejas has a top speed of mach 1.6(demonstrated till today) at service ceiling(15000 meters)

and 1350 km per hour speed at sea level.


In fact the position is exactly opposite,

with lesser power to weight ratio tejas ( mk-1 itself) has demonstrated top speeds ,(mk-2 will have way higher TWR ratio!!!)

that closely match the speeds of published top speeds of rafale ,

which has twenty percent more advantage in TWR!!!)

in both sea level and service ceiling, So which airframe is more draggier?



I know you and
@Srinivas_K
are a frequent poster in a forum ACROSS THE BORDER where a few guys (one named Sancho , I think) often makes the unsubstantiated point of tejas having excess drag and so on,,,,,

Please make the same post I highlighted with bold letters there and you will be amused to see the reply,

So where is the drag?

There are more drag queens in forums thumping the desks about excess drag of tejas than the original drag present in tejas air frame.

All these guys are arguing in reverse. interference and wave drags(two very important component of total drag) will always be more for delta canards than a compound delta, sine canards are present another plane of resistance to oncoming highspeed wind.

ADA found out after wind tunnel testing for a small fighter design like tejas developed under a specific ASQR need from IAF canards give no notable advantage compared to the weight penalty it imposed. it was stated by ADA on record.

it is an elementary law of aerodynamics. pity people don't even know that and misleading people with motivated campaigns to dump their prejudice on tejas .

 

[Srinivas_K]

I have no idea why some think tanks degrade Tejas ..... I have raised this point to them ..... seems they do not have confidence in Indian designs.

But to me Tejas is one of the lightest and Lethal fighters out there.

The advantage with Tejas is, it fits perfectly to the the role of interceptor and is more than enough to fill the light fighter category of IAF.

Tejas is a test bed for the technologies that are going to be incorporated in AMCA and other fighter programs as well.

The experience gained from LCA Tejas is a very valuable one, India not only perfected the light and Carbon material technologies but also gained crucial knowledge of flight control laws.

Tejas is a perfect fit to make it a UAV in the near future. The design suits this fighter to become a UAV by simple removal of Pilot apparatus.

both tejas mk-1 and mk-2 (of course weapon load may vary)can take advantage of it. in US the external stealth pods , since rafale, super hornet, f-15 eagle will one day carry them irrespective of their TWR.

But these external weapon pods are mostly used in air to air interception missions till now, since weight of air to air missiles are far lesser than heavy ground bombs weight is not a big issue.

Actually there are some hilarious discussions going on over many forums over the missing eight hard point of tejas.

Now ask those guys one simple questions, with 9 ton load carrying capacity rafale has 14 hard points.
With 3.7 ton capacity tejas mk-1 has seven hard points,

With 5 ton load carrying caapcity tejas mk-2 will have 7 hard points. So why people are disappointed with this?

You can rest assure that there will be no reply from many "fake experts claiming superior knowledge."

Also in the same way there are many guys who claim to have "specialized knowledge" of tejas's excess drag which is causing so many problems for tejas in their imagination.

Ask them one simple question,

With a thrust to weight (empty weight +half internal fuel+ two WVR missiles weight taken as norm) ratio of 1.2

rafale has a top speed of mach 1.8 at its service ceiling (15235 meters),

and 1390 km per hour at sea level,

Vs

With a Thrust to weight ratio (empty weight +half internal fuel+ two WVR missiles weight taken as norm) of 0.97,

tejas has a top speed of mach 1.6(demonstrated till today) at service ceiling(15000 meters)

and 1350 km per hour speed at sea level.


In fact the position is exactly opposite,

with lesser power to weight ratio tejas ( mk-1 itself) has demonstrated top speeds ,

that closely match the speeds of published top speeds of rafale ,

which has twenty percent more advantage in TWR!!!)

in both sea level and service ceiling, So which airframe is more draggier?



I know you and
@Srinivas_K
are a frequent poster in a forum ACROSS THE BORDER where a few guys (one named Sancho , I think) often makes the unsubstantiated point of tejas having excess drag and so on,,,,,

Please make the same post I highlighted with bold letters there and you will be amused to see the reply,

So where is the drag?

There are more drag queens in forums thumping the desks about excess drag of tejas than the original drag present in tejas air frame.

 

[ersakthivel]

Also grippen's top speed of mach 2 was achieved at 15240 meters in cold sweedish conditions,
opposed to tejas's mach 1.6 achieved at 15000 meters in hot indian climatic condition.

It is common knowledge that the for the same lift drag configuration top speeds increase with the altitude and hot weather significantly saps a fighter's engine thrust,

So if we take both these factors into account there is no point in saying tejas airframe is draggy.

 

[ersakthivel]

Also grippen's top speed of mach 2 was achieved at 15240 meters in cold sweedish conditions,
opposed to tejas has been tested to mach 1.6 at 15000 meters in hot indian climatic condition.

It is common knowledge that the for the same lift drag configuration top speeds increase with the altitude and hot weather significantly saps a fighter's engine thrust,

So if we take both these factors into account there is no point in saying tejas airframe is draggy.

Also grippen C's top speeds at sea level is mach 1.06 i.e 1300 Km per hour,

but tejas mk-1 itself has crossed mach 1.1 ,i.e 1350 Km per hour at sea level under hot weather conditions during Goa tests,

Both Mig-29 and Su-30 MKI also have the same 1350 Km per hour sea level top speed in the hot indian condition.

Add to that the fact tejas has a significantly larger wing area (to lift higher loads in lesser air density indian hot weather conditions ,and to have a better instantaneous turn rate for a first shot with HMDS enabled high off bore WVR missiles in close combat as well as ) than grippen, then the higher top speeds achieved by tejas in indian hot sea level conditions is even more creditable.

So despite the higher skin friction drag from high wing surface of area tejas achieved 1350 Km per hour at sea level points to optimum lift drag ratio for the air frame.

So there is no technicl basis to say tejas is draggy

SO comparing top speeds achieved in cold weather conditions by other fighters ,

to top speeds achieved by tejas in hot weather conditions ,

and concluding tejas is a draggy air frame is a factually incorrect statement.

 

[sathya]

both tejas mk-1 and mk-2 (of course weapon load may vary)can take advantage of it. in US the external stealth pods , since rafale, super hornet, f-15 eagle will one day carry them irrespective of their TWR.



Actually there are some hilarious discussions going on over many forums over the missing eight hard point of tejas.


Ask them one simple question,


I know you and
@Srinivas_K
are a frequent poster in a forum ACROSS THE BORDER where a few guys (one named Sancho , I think) often makes the unsubstantiated point of tejas having excess drag and so on,,,,,

I am sure you are mistaking me for some one.. I use my same name at all places
I read few forums , hardly post anywhere ..
Btw I am firm supporter of Tejas... Which I would wouch for replacing all 3 rd generation air crafts right now..

 

[ersakthivel]

I am sure you are mistaking me for some one.. I use my same name at all places
I read few forums , hardly post anywhere ..
Btw I am firm supporter of Tejas... Which I would wouch for replacing all 3 rd generation air crafts right now..

No, I am not mistaking you or accusing you of anything. I was referring to few other guys who make such baseless statements. Not you.

So please don't mistake me . I have nothing against you personally,

 

[abhi_the _gr8_maratha]

many raised question when iaf stated 45 million dollar is price of single mirage update
.
mirage costing so much for upgrade because its design is not open like tejas
.
because of open architecture drdo can change any equipment whenever they want ,what they have to do is to develop advance equipment but the size must be same of it with the equipment that's used in tejas for eg pesa radar of tejas mk1 later will be change with aesa
.
this will lead to a less costly but equal effective upgrade and tejas later can be incorporated with many new advanced equipment

 

[ersakthivel]

CLmax can be increased by LERX, strakes, LE devices, Dogtooth and TE flaps. It can also be increased by reducing the sweep angle or selecting a thicker wing. depending on the speed that you want to achieve, the thickness can't be altered and you can only play around with sweep angle.

Use of any of those devices mentioned above also lead to increased drag due to skin friction drag arising out of their surfaces.
LREX are , strakes, flaps, LE devices all create vortex to increase lift . Cranked delta also creates vortex flow to increase lift. So if using vortex to increase CLmax is wrong in cranked delta(as explained below) then it is equally wrong in using all the devices explained above!!!

Use of votices to increase CLmax results in increase of drag.

The above point was clearly belied by compound delta low wing loading F-16 XL when it performed well over cropped delta high wing loading regular F-16.

LCA uses LE slats, cropped delta leading edge and levcon to increase its CLmax but it has a very high sweep angle. The front part of wing is swept at 50* while the outer part is swept at 62.5* giving it an effective sweep of 53*. On top of that it is a tailless design.

The design requirement behind such wing sweep is known only to IAF and ADA. Even pakfa and F-22 have higher wing sweep angle than F-15 , F-16 and Su-30 MKI. that does not mean they are poor performers.

People get confused with wing loading as a parameter for maneaverability but the correct word is CLmax. You can have a higher CLmax for a smaller wing and yet outperform an ac with lower wing loading. LCA has a wing area of nearly 38 sqm but look at what it lifts compared to 28 sqm of F-16 blk52/Gripen.

Low wing loading is used to get higher CLmax. The F-16 has a way higher thrust engine , thats why it lifts more weight. F-22 and PAKFA have more wing area than F-16 and grippen . Does that mean they are inferior designs?

In cold climates grippen C/D lifts 14 tons MTOW, In much hotter indian climate tejas mk-1 alone lifts 13.5 tons. We dont yet know what grippen lifts at indian hot climatic conditions.

Tejas has 38 sq meter wing area , while gripen C/Dhas 30 sq meter area almost a difference of twenty percent , So grippen has close to 25 percent lower wing are than tejas but the difference in MTOW is just 8 percent, (even without taking into consideration the hot climate penalty for tejas mk-1, if we take that into account difference will reduce to below 5 percent).so the point that smaller wings can lift more load can not be supported by any formula.

Gripen C is nearly as heavy as LCA at 6800kgs. It has smaller wing but it generates much higher CLmax for that small wing due to lower sweep angle of 45* and CC canards. Both ac are RSS FBW designs. a canard design needs about 25% less thrust for a similar sized ac with tail or tailless config. This explains that Gripen C with smaller wing, lower thrust still lift 5500 kgs of load compared to LCA's 3600 kgs.

If a canard design needs 25 percent less thrust then grippen C/D must lift 25 percent more weight than tejas MTOW(i.e 17 tons!!!) . Clearly the above statement is factually wrong since grippen onlt lifts 14 tons. grippen may have 4 Kn lesser powered engine, but since grippen's 14 ton figures are for cold swiss climates extra 4 Kn thrust in tejas can be factored off to hot indian climatic conditions .

If delta canards require 25 percent less power, why does both tejas and grippen have almost the same top speed at sea level. Shouldn't grippen have 25 percent more topspeeds at sea level.

This sea level speed spec alone can prove everything posted as mistakes of tejas as false. tejas has achieved 1350 Km per hour under hot goa conditions, not under cold conditions as grippen does at sea level. this one statement alone belies most of the arguments against tejas.

because hot humid climate of india reduces engine thrust. So tejas achieving almost the same speed of grippen C/D in these hot conditions is even more creditable.

If compound delta of tejas is so draggy, and 25 percent more power hungry,

high wing sweep of tejas was so draggy,

high wing area of tejas is a huge drag penalty as listed above,

how could tejas mk-1 have almost the same top speed as that of gripen C/D at indian demanding hot climate sea level flight during flutter test?

 

[ersakthivel]

If compound delta of tejas is so draggy, and 25 percent more power hungry,

high wing sweep of tejas was so draggy,

high wing area of tejas is a huge drag penalty as listed above,

how could tejas mk-1 have almost the same top speed as that of rafale

which has lesser wing area and wing loading than tejas mk-1,

lesser wing sweep angle than tejas mk-1,

has a canard delta configuration which is supposed to give 25 percent more efficient power usage,

at indian demanding hot climate sea level flight during flutter tests?

So the sentiments expressed in the first three lines(in various forum threads and countless articles) are certainly wrong. The design of tejas is as good or as bad as rafale or grippen is the truth. With higher powered engine in tejas mk-2 the full potntial of the platform can be brought to the fore.








With a thrust to weight (empty weight +half internal fuel+ two WVR missiles weight taken as norm) ratio of 1.2

rafale has a top speed of mach 1.8 at its service ceiling (15235 meters),

and 1390 km per hour at sea level,

Vs

With a Thrust to weight ratio (empty weight +half internal fuel+ two WVR missiles weight taken as norm) of 0.97,

tejas has a top speed of mach 1.6(demonstrated till today) at service ceiling(15000 meters)

and 1350 km per hour speed at sea level.






Not only that some people express even more lies like choosing the same nose cone dia of raflae in a small fighter like tejas and choosing a tail less canard less compound delta wing form over delta canard wing form is the reason for excess drag in tejas air frame.

But the same set of rebuttals made in all of my posts in this page also prove their claims wrong.


If their claims on excess drag in tejas is true tejas can not achieve 1350 Km per hour at the sea level flight and it can not lift 13.5 tons in demanding hot and humid indian climatic conditions.The fact it does proves that there is nothing wrong in tejas airframe regarding the drag.Whatever skin friction drag is there due to excess wing area produces corresponding lift to cancel that drag and give a overall beneficial performance .

Not only that a low wing loading and high TWR combo does has its unique advantage of high instantaneous turn rate which is the deciding factor in who fires his high off boresight WVR missile like R-73 with the help of HMDS enabled first look , first shot capability,



because this unique factor gives tejas a high instantaneous turn rate which is critical in turning fast in an instant and get a lock on your opponent to shoot first.

Not only that absence of canards will definitely reduce RCS emissions to modern ASEA radar in all directions. And the bigger Nose cone dia of tejas than grippen and the higher powered higer dia radar ,

that could be placed there gives tejas some edge over grippen C/D in the crucial spec of who detects who first with a more powerful radar and less overall RCS emission.

So tejas will hold its own against even the much powerful and costlier rafale in this count because both have the almost same nose cone dia for radar

 

[halloweene]

.Just for info, Rafale was tested up to near mach 2.1. Operating speed and max aerodynamic speeds are different things. Its loading can be higher than 9500 Kgs, even with full internal fuel. Etc. Why do you always forget range btw.

Plz notice i didnt say anything bad to Tejas.

 

[brahmastra11]

With due respect I am not saying anything bad to Rafale

But we can place 3 Tejas in place of 1 Rafale and can operate everything Rafale can do. You accept or not hope many will accept this truth.

.Just for info, Rafale was tested up to near mach 2.1. Operating speed and max aerodynamic speeds are different things. Its loading can be higher than 9500 Kgs, even with full internal fuel. Etc. Why do you always forget range btw.

Plz notice i didnt say anything bad to Tejas.

 

[Neil]

 

[SajeevJino]

With due respect I am not saying anything bad to Rafale

But we can place 3 Tejas in place of 1 Rafale and can operate everything Rafale can do. You accept or not hope many will accept this truth.

If with Tejas ..Three Pilots ,Three Hangers , more amount of Fuel , More No. of Engines and Missiles .More No of Ground Crews ..More Operating costs

If comes Rafale 75% of Savings

 

[brahmastra11]

So your analogy says 1 Rafale can carry the load of 3 Tejas and can be in air 3 times that of 1 Tejas flight..

I am not interested in childish barbs and dont want to get into Rafale and Tejas comparison further as this thread is to discuss all about Tejas development.. My last post was only to address benefit of IAF owning indigenous Tejas in place of Rafale.

If with Tejas ..Three Pilots ,Three Hangers , more amount of Fuel , More No. of Engines and Missiles .More No of Ground Crews ..More Operating costs

If comes Rafale 75% of Savings